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Analysis of autenthicity of food products with fruit component
Prachárová, Adriana ; Mikulíková, Renata (referee) ; Márová, Ivana (advisor)
The aim of this thesis was to determine the authenticity of fruit food for infants using molecular and instrumental methods. In the experimental part, plant DNA isolations from fruit leaves (peaches, apricots, plums and apples) and bananas were performed. Further, DNA was isolated also from five commercial products, and from model mixtures that were prepared in terms of content identical to the commercial mixtures. The isolated DNA was characterized and verified by qPCR with plant DNA-specific ITS2 primers. Three triple primer pairs were selected, and their specificity was evaluated when performing multiplex PCR. This method makes it possible to detect more types of fruit in one reaction, reducing the economic and time requirements for detection. As none of the selected primer pairs were sufficiently specific for the apricot, the evidence from the plum and peach was further realized using duplex PCR. High resolution melting curve analysis was used for better DNA type recognition. Subsequently, agarose gel electrophoresis was performed to analyse the fragment lengths. Furthermore, experiments have been made to identify some specific phenolic substances in commercial and model fruit mixtures by HPLC. Since phenolic substances are degradable under unsuitable storage conditions, the presence of individual compounds was not detected by this method.
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Addition of probiotics and algae extracts to baby foods
Liová, Alexandra ; Szotkowski, Martin (referee) ; Němcová, Andrea (advisor)
This bachelor thesis deals with the selection of a suitable combination of probiotic culture with algae extracts as an addition to the baby formula and the application of the optimal composition of baby formula. Arame, wakame, hijiki and kombu seaweeds were selected for these purposes. The theoretical part is focused on the proper nutrition of children, their deficiencies and possible diseases. Subsequently, it deals with the characterization of probiotic cultures and their importance in the child's nutrition. Last but not least, the theoretical part characterizes the individual seaweeds, their nutritional composition and also their importance in the child's nutrition. In the experimental part, samples of selected algae were first analyzed in terms of saccharides, insoluble fiber content, fructooligosaccharides and -glucans or pigment content. A sample of inulin, a commonly used prebiotic in probiotic products, was used as a reference component. An important analysis of this experimental part was to determine the effect of algal extracts on the viability and growth of probiotic bacteria. Subsequently, a model digestion of a mixture of probiotics and algal extracts was performed, and the condition of the probiotic cells was evaluated during digestion and after digestion by measuring turbidity and flow cytometry. Finally, not only the optimal combination of algae extract and probiotic culture was proposed, but also the possibility of improving the long-term viability of probiotic cells in combination with algal extracts.
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Development and optimization of methods for detection of selected fruit species in foodstuffs
Šlosárová, Katarína ; Wikarská, Monika (referee) ; Fialová, Lenka (advisor)
Various types of adulteration of food products are becoming more frequent in the food industry than ever. That is no different for fruit products. This bachelor thesis deals with the detection of mango in fruit purées for infants through the use of qPCR and HPLC in three selected commercial products and their prepared replicas. Within the framework of molecular biology, different primers specific for mango were tested. Several primers, which were the most suitable for the demonstration of mango in fruit purées, were selected based on the course of the qPCR reaction, the size of the amplified product, specificity, and sensitivity. Using these primers, the presence of mango was proven in all six analysed samples. Regarding the instrumental part of the work, a rapid and simple method of extraction of phenolic compounds for their analysis by HPLC was tested, which has been previously successfully used on another plant matrix. This method was proved to be unsuitable for the extraction of phenolic compounds from fruit purées for the purpose of their authenticity verification using HPLC [1].
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Determination of selected red fruit species in plant-based food using multiplex PCR and instrumental methods
Vybíralová, Natálie ; Langová, Denisa (referee) ; Fialová, Lenka (advisor)
In many cases food is becoming the subject of adulteration, including fruit products that contain raspberries, strawberries and blueberries. This bachelor thesis is focused on the detection of strawberries, rapsberries and blueberries in model and commercial baby food products using multiplex PCR and HLPC. The theoretical part of this thesis is focused on composition of red fruits, their importance in human nutrition and especially about isolation of DNA from plant material. The aim of the experimental part of work was the analysis of selected commercial and model mixtures fruit purees containg raspeberries, strawberries and blueberries using instrumental and molecular biological methods. The results of these metods are compared. Commercial purees were bought in retail grocery shop. Model mixtures of these purees were prepared in our laboratory. DNA was isolated from fruit purees after and it’s amplifiability was comfirmed, it was successfully used in multiplex PCR to confirm the presence of raspberries, strawberries and blueberries in fruit purees. In the instrumental part, certain phenolic substences which are specific to red fruits were detected by HPLC in model and commercial mixtures.
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Technology of fruity baby food and its monitoring
Gállová, Eva ; Babák, Libor (referee) ; Vitoulová, Eva (advisor)
This bachelor thesis is showing technological procedure of fruit baby food production and its monitoring. It specifies the list of used fruits and ingredients for the production. It analyses particular pocedures of stuff processing and and production process from bringing the stuff to the factory to ready products delivery. It analyses toxic impacts and contamiators checkout as well, that may appear in fruit baby meals. There is a legislation part concerning manufacturing process of agricultural production and food inspection of Czech republic that showed defects on baby ready meals.
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Detection of undeclared fruit species in foodstuffs using methods of molecular biology and instrumental methods
Svobodová, Petra ; Wikarská, Monika (referee) ; Fialová, Lenka (advisor)
This thesis is focused on the detection of apple component in fruit-based baby food. The theoretical part deals with the fruit itself – the apple; food adulteration as a reason for the control of food composition and methods, both instrumental and those of molecular biology, by which food adulteration can be detected. In the experimental part, commercial products containing apple puree were purchased and model mixtures were prepared as replicas of the purchased products. DNA was isolated from these samples, its amplifiability was verified, and the presence of the apple component was detected after the selection of suitable species-specific primers. Methanol extracts for HPLC were prepared from the above-mentioned samples using a procedure previously used for the extraction of phenolic substances from apple pulp [1]. Using this analysis, apple in fruit purees was to be identified using phloridzin as a marker for the presence of the apple component. The result was a successful detection of the apple component in both commercial products and model mixtures using qPCR. However, the tested method of phenolic substance extraction proved to be unsuitable for use in the analysis of fruit purees, as phloridzin was not detected either in the apple puree extract or in the model mixtures to which this puree was added.
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Analysis of autenthicity of food products with fruit component
Prachárová, Adriana ; Mikulíková, Renata (referee) ; Márová, Ivana (advisor)
The aim of this thesis was to determine the authenticity of fruit food for infants using molecular and instrumental methods. In the experimental part, plant DNA isolations from fruit leaves (peaches, apricots, plums and apples) and bananas were performed. Further, DNA was isolated also from five commercial products, and from model mixtures that were prepared in terms of content identical to the commercial mixtures. The isolated DNA was characterized and verified by qPCR with plant DNA-specific ITS2 primers. Three triple primer pairs were selected, and their specificity was evaluated when performing multiplex PCR. This method makes it possible to detect more types of fruit in one reaction, reducing the economic and time requirements for detection. As none of the selected primer pairs were sufficiently specific for the apricot, the evidence from the plum and peach was further realized using duplex PCR. High resolution melting curve analysis was used for better DNA type recognition. Subsequently, agarose gel electrophoresis was performed to analyse the fragment lengths. Furthermore, experiments have been made to identify some specific phenolic substances in commercial and model fruit mixtures by HPLC. Since phenolic substances are degradable under unsuitable storage conditions, the presence of individual compounds was not detected by this method.
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Determination of selected red fruit species in plant-based food using multiplex PCR and instrumental methods
Vybíralová, Natálie ; Langová, Denisa (referee) ; Fialová, Lenka (advisor)
In many cases food is becoming the subject of adulteration, including fruit products that contain raspberries, strawberries and blueberries. This bachelor thesis is focused on the detection of strawberries, rapsberries and blueberries in model and commercial baby food products using multiplex PCR and HLPC. The theoretical part of this thesis is focused on composition of red fruits, their importance in human nutrition and especially about isolation of DNA from plant material. The aim of the experimental part of work was the analysis of selected commercial and model mixtures fruit purees containg raspeberries, strawberries and blueberries using instrumental and molecular biological methods. The results of these metods are compared. Commercial purees were bought in retail grocery shop. Model mixtures of these purees were prepared in our laboratory. DNA was isolated from fruit purees after and it’s amplifiability was comfirmed, it was successfully used in multiplex PCR to confirm the presence of raspberries, strawberries and blueberries in fruit purees. In the instrumental part, certain phenolic substences which are specific to red fruits were detected by HPLC in model and commercial mixtures.
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Development and optimization of methods for detection of selected fruit species in foodstuffs
Šlosárová, Katarína ; Wikarská, Monika (referee) ; Fialová, Lenka (advisor)
Various types of adulteration of food products are becoming more frequent in the food industry than ever. That is no different for fruit products. This bachelor thesis deals with the detection of mango in fruit purées for infants through the use of qPCR and HPLC in three selected commercial products and their prepared replicas. Within the framework of molecular biology, different primers specific for mango were tested. Several primers, which were the most suitable for the demonstration of mango in fruit purées, were selected based on the course of the qPCR reaction, the size of the amplified product, specificity, and sensitivity. Using these primers, the presence of mango was proven in all six analysed samples. Regarding the instrumental part of the work, a rapid and simple method of extraction of phenolic compounds for their analysis by HPLC was tested, which has been previously successfully used on another plant matrix. This method was proved to be unsuitable for the extraction of phenolic compounds from fruit purées for the purpose of their authenticity verification using HPLC [1].
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|
|
Detection of undeclared fruit species in foodstuffs using methods of molecular biology and instrumental methods
Svobodová, Petra ; Wikarská, Monika (referee) ; Fialová, Lenka (advisor)
This thesis is focused on the detection of apple component in fruit-based baby food. The theoretical part deals with the fruit itself – the apple; food adulteration as a reason for the control of food composition and methods, both instrumental and those of molecular biology, by which food adulteration can be detected. In the experimental part, commercial products containing apple puree were purchased and model mixtures were prepared as replicas of the purchased products. DNA was isolated from these samples, its amplifiability was verified, and the presence of the apple component was detected after the selection of suitable species-specific primers. Methanol extracts for HPLC were prepared from the above-mentioned samples using a procedure previously used for the extraction of phenolic substances from apple pulp [1]. Using this analysis, apple in fruit purees was to be identified using phloridzin as a marker for the presence of the apple component. The result was a successful detection of the apple component in both commercial products and model mixtures using qPCR. However, the tested method of phenolic substance extraction proved to be unsuitable for use in the analysis of fruit purees, as phloridzin was not detected either in the apple puree extract or in the model mixtures to which this puree was added.
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